Filtering bag for brewing coffee and method of making such bag



April 1959 G. J. o. WELINBERGER 3,437,540

FILTERING BAG FOR BREWING COFFEE AND METHOD OF MAKING SUCH BAC- FiledMay 5, 1966 Sheet of 2 INVENTOR. Gay (/OH/V 04 0/ W54 //v 5,5961% April1969 e..1;o. WELlN-BERGER 3,437,540

FILTERING BAG FOR BREWING COFFEE AND MEIHOD OF MAKING SUCH BAG Filed May5. 1966 Sheet 2 of 2 FIG. 2

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nite States Patent FILTERING BAG FOR BREWING COFFEE AND METHOD OF MAKINGSUCH BAG Guy John Olof Welin-Berger, Parkgrand 4, Nacka, Sweden FiledMay 5, 1966, Ser. No. 547,935

Claims priority, application Sweden, May 7, 1965,

6,022/ 65 Int. Cl. B321) 7/ 14 US. Cl. 156-269 2 Claims ABSTRACT OF THEDISCLOSURE Coffee-brewing filter bags are formed of filtering paper byadhering together two elongated webs of filtering paper alongalternately oppositely inclined lines with the more closely adjacentends of the inclined lines interconnected by stripes of adhesiveparallel to the length of the webs. Coffee bags are then cut out alonglines that follow the middle of the lines of adhesive, with an open endcut out along a circular are opposite the bottom edge of the bag. Thebag blanks are thus cut from the webs in the pattern shown in thedrawings to minimize waste of material.

This invention relates to a filtering bag for brewing coffee and has forits object to form such bag in a manner which renders possible simpleproduction with a minimum of consumption of paper. The invention alsorelates to a manner of making the bag.

In its broadest aspect the filtering bag according to the invention ischaracterized in that it consists of two layers of filtering paper whichare pasted together along the bottom and two lateral margins of the bag.

In its broadest aspect the manner of making the bag is characterized byproviding one of two layers of filtering paper with an adhesive alongstripes corresponding to the bottom and lateral margins of the bag,pasting the layers together, punching or cutting the bag out from thelayers so that the bag will consist of the two layers which are pastedtogether along the bottom and the lateral margins. Mass production ispossible by providing one or both layers with adhesive stripes defininga plurality of bags such that the bottom portion of every second baglies at one margin of the layers and the bottom portions of the otherbags lie at an opposite margin of the layers. In this case the adhesivestripes for the various bag blanks can be placed close to each other atthe lateral margins so that the paper can be effectively utilized.Advantageously the layer consists of paper webs to which adhesivestripes can be applied corresponding to a plurality of rows of bagblanks. The stripes of each row can be arranged such that the bottomedge of every second bag blank faces one longitudinal edge of the websand that the bottom edges of the other blanks face the otherlongitudinal edge. Four or eight or even more rows can be arranged alongthe two webs.

The bag blanks can be punched out from the layer webs which are puttogether and connected to each other along the stripes, where thepunched cuts are placed in the middle of each adhesive stripe or midwaybetween two parallel adhesive stripes and further along an arcuate linedefining the mouth of the bag.

Additional features of the invention and advantages obtained therebywill appear from the following description of an embodiment illustratedin the accompanying drawing. FIG. 1 is a plan view of a pair of paperwebs pasted together along stripes such that the stripes contain aplurality of rows of bag blanks to \be punched out from the webs. FIG. 2shows how the bag blanks can be punched out so as to reduce the wastageto a minimum. FIGS. 3 and 4 are perspective views of the finished bag.

In the example illustrated in FIG. 1 two webs of filtering paper areassumed to be placed in superimposed positions and pasted together alongstripes which define figures substantially in the form of a V. Four rowsof FIG- URES 1, 2, 3 and 4 are illustrated, but any number of rows maybe chosen. In each row V-shaped figures are arranged such that thevertex of the V corresponding to the bottom of the bag of every secondfigure faces one longitudinal side edge 5 of the webs and that thevertices of the V:s of the other figures are facing the other side edge6. Adhesive stripes 7, 8 located at the lateral margins of a bag extendon the bag blank parallel and close to adjacent corresponding adhesivestripes 9, 10 on the adjacent bag blanks in the same row. Thechain-dotted line 11 denotes the outline of a bag blank. The bag blankis to be punched out from the webs along said outline. The punching line11 extends midway between the adhesive stripes 7, 9 and the adhesivestripes 8, 10 and passes along the adhesive stripe at the bottom of thebag blank. The upper edge of the bag blank is defined by a punching linewhich is a curve 12 in the form of an arc of a circle. At this placethere is of course no adhesive stripe because the bag is to be open.

FIG. 2 illustrates two rows 1, 2 of figures to be punched out. The row 1comprises a pair of adjacent figures A and B. In the adjacent row 2 afigure to be punched out is denoted at C. The figure C in the row 2 islocated opposite the figure A in the row 1 and has its mouth line edge12 directed toward the bottom edge line 14 of the figure A. In order toreduce the wastage of paper material as much as possible, the distancebetween the rows at end 2 should be as small as possible. The distanceis defined by the minimum distance a. between the lines 12 and 14 thatis allowed by the punching tool, and consideration has to be taken toobtaining neat edge lines. With regard to the wastage between thepunching rows 1 and 2 it is desirable also to minimize the distance bbetween any mouth edge line 12 in a row, such as 2 and the confrontingmouth edge lines of the figures in the row 1, the last-named lines beinglocated on either side of the figure in the row 1 that registers withthe said figure in the row 2. The ideal configuration with regard to thewastage of material between the rows is obtained if the distance a isequal to the distance b. However, consideration is also to be paid tothe wastage of material at the margins of the paper webs. In FIG. 2 oneedge line 5 only is indicated; but similar conditions apply to the otheredge. The wastage of material between the rows 1 and 2 is represented bya hatched surface 15 and the wastage of material at the edge 5 isrepresented by a hatched surface 16. By displacing the figures to bepunched out in the various rows with respect to each other it ispossible to obtain positions of the figures relative each other andrelative to the edge lines of the paper webs resulting in a minimum ofwastage. Regarding the wastage at the margins and depending on theoutlines of the bag blanks it may be possible that the distance b willbe greater than the distance a. Otherwise, the distance 0 at the figureB in FIG. 2, between the punch figures which have their bottom edge line14 facing the edge 5 of the web might become too great. By having themouth edge lines of the figures to be punched out in each row in themanner described alternatingly directed toward and away from the edge ofthe web and by making the distance between the row, such as the row 1,located nearest the edge line and this edge line as small as possibleand by making the distance between the rows as small as possible aminimum of wastage of material is ensured. In other words, the papermaterial can be utilized to the highest possible extent.

A still better utilization can be obtained by a certain other scheme ofthe outline of the bag blank, viz., if the mouth edge lines 12 arestraight insead of arcuate and located such as to coincide with the edgeof the web. In this case the bottom edge line 14 may also be straightand parallel to the edge of the web. However, a straight punching line12 for the mouth edge results in a bag having concave lips because thelateral margins are not parallel to each other whereas the punching line12 in the form of an arc of a circle and results in a bag lip which inthe finished bag lies in a single plane. For this reason a punching line12 in the form of an arc of a circle is preferred.

To obtain a high capacity of the punching operation in a single punchingmachine, the machine may be constructed so as to be able simultaneouslyto punch a plurality of pairs of webs pasted together. In this case thevarious webs are suitably marked so that it is possible to make surethat the adhesive stripes of a web are registering with the adhesivestripes of the other webs or Web.

In FIG. 1 an adhesive stripe is shown for each bag blank, and thepunching line 11 extends between parallel adhesive stripes 7, 9 and 8,10 elongated at the lateral margins of adjacent bag blanks. Instead oftwo parallel adhesive stripes a single wide adhesive stripe may beapplied with the punching line extending midway thereof.

What I claim is:

1. A method of making coffee-brewing filter bags of filtering papermaterial having two symmetric side walls of generally V-shapedinclination to each other with a wide end edge substantially coincidingwith a circle sector to form a circular arc and a narrow bottom edge located opposite to the circular arc end edge, the two side walls beingglued together along the radially extending side edges and the bottomedges of the side walls, comprising the steps of applying a plurality ofgenerally V- shaped stripes of adhesive material corresponding to saidside edges and bottom edges onto at least one of a pair of elongatedwebs, superimposing the webs to unite them along said V-shaped stripesand bottom edges, the V- shaped stripes being arranged to form a patternbetween the two superimposed webs in which the symmetry axes of all theareas between the V-shaped stripes are positioned at right angles to thelongitudinal direction of the webs and the stripes form at least twolongitudinal rows of V-shaped stripes with the bottom edge stripeportions facing alternately to the one or other side edge of the webs toform a zig-zag shaped line of adhesive material in each row, allV-shaped stripes which have their bottom edge portions facing one of theside edges of the webs being located in transverse rows with thesymmetry axes of the areas between the V-shaped stripes in eachtransverse row substantially coinciding with each other, and severingthe two webs along said zig-zag shaped adhesive lines of eachlongitudinal row and along said circular arcs extending between the endsof the bottom edge stripe portions.

2. A method as claimed in claim 1, and applying said bottom edge stripesof adhesive and severing said bottom edges along lines substantiallyparallel to said longitudinal direction of the webs.

References Cited UNITED STATES PATENTS 2,237,346 4/1941 Gilfillan156-291 2,272,530 2/1942 Patterson 206O.5 2,622,055 12/1952 Lieder156-269 2,935,241 5/1960 Brady 93-35 3,172,796 3/1965 Giilker 156-269DOUGLAS J. DRUMMOND, Primary Examiner.

US. Cl. X.R.

